A glass container forming machine of the I.S. type forms a glass container at a section of a multiple section machine in a two-step operation. In the first step, a hollow preform of the finished container, which is usually called a parison or blank, is formed from molten glass by blowing or pressing a gob of glass within a suitable mold, and the parison is usually formed in an inverted orientation, that is, with its open end down. The parison is then transferred by an inverting mechanism, which is rotated through an arc of 180.degree., to a blow mold station where the parison is blown, within the confines of a suitable mold, to its final configuration.
The finish portion of the container, that is, the portion of the container surrounding its open end, which is threaded or otherwise configured to permit a closure to be secured to the container, is formed by a neck ring assembly. The neck ring assembly is made up of a pair of 180.degree. ring sections that collectively fully surround the portion of the container being formed that is to be its finish, and the neck ring assembly is carried by the invert arm and travels with the parison as it is transferred from the blank mold to the blow mold. The neck ring sections are able to separate with respect to one another to permit a container to be withdrawn therefrom, and then to close with respect to one another in a circumferential pattern to form a finish in the next parison to be processed therethrough.
The opening and closing of the neck ring sections with respect to one another are guided by a circumferentially continuous ring, called a guide ring, that is received in a slot in the neck ring assembly which is defined by mating slot portions of the neck ring sections. A typical guide ring has a flange section that has a relatively large diameter, but is relatively thin in an axial direction, and a small diameter hub extending from the flange section, which is relatively thick in its axial direction. Heretofore, it was customary to fabricate such guide rings as single pieces from a hardened steel alloy.
The flange of a steel guide ring, as heretofore described, is slidably received in the mating slot portions of the neck ring sections and must be periodically lubricated to permit the required relative sliding motion between the guide ring and the neck ring sections as the neck ring sections open and close with respect to one another. Heretofore, it was customary to provide such lubrication by having the forming machine operator periodically, e.g., every 15 minutes, swab the neck rings with a liquid suspension of graphite particles. However, the liquid swabbing procedure heretofore employed in lubricating I.S. forming machine neck rings, as described above, has a number of disadvantages.